QT dispersion (QTD) on 12-lead ECGs has been proposed as a marker of malignant ventricular tachyarrhythmias, and increased QTD has been reported in long QT syndrome (LQTS). On the other hand, it has been demonstrated that transmural dispersion is associated with ventricular tachyarrhythmias in an experimental model. However, the precise type of QTD or transmural dispersion that contributes most to ventricular tachyarrhythmias in patients with LQTS remains unclear. We evaluated 27 patients with acquired LQTS. These patients were divided into two groups: group A (n =12), patients with polymorphic ventricular tachycardia [torsades de pointes (TdP)], and group B (n =15), patients without TdP. The QT intervals were corrected using Bazett's formula. QTD was measured as the difference between the maximum and the minimum QT intervals, and T wave peak-to-end interval divided by the QT interval (Tpe) in the V5 lead was measured as a new index. Both the corrected QTD (QTDc) and Tpe were significantly larger in group A than in group B. Logistic regression analysis revealed that a reliable predictor for TdP in the QT variables in these patients was not QTDc but Tpe. Cumulative frequency distributions revealed that a Tpe of 0.28 is a good cut-off point for TdP. Tpe did not correlate with the corrected maximum QT interval, whereas the QTDc did correlate with this parameter. In conclusion, Tpe may be the best predictor for TdP in patients with acquired LQTS.

SummaryBackground: Patients with hypertrophic cardiomyopathy (HCM) associated with a deletion of lysine 183 (K183del) in the cardiac troponin I (cTnI) gene suffer sudden cardiac death at all ages. However, the correlation between QT variables and sudden cardiac death in these patients remains uncertain.Hypothesis: We evaluated the correlation between QT variables and sudden cardiac death and/or ventricular tachyarrhythmia (SCD/VT) in patients with HCM associated with the cTnI mutation.Methods: We analyzed 10 probands with HCM associated with the cTnI gene K183del and their family members. The subjects were divided into three groups: Group A (n = 7), mutation carriers with SCD/VT; Group B (n = 16), mutation carriers without SCD/VT; Group C (n = 24), no mutation carriers. QT intervals were corrected using Bazett's formula.Results: Maximum QTc and corrected QT dispersion were significantly longer in Groups A and B than in Group C. However, there were no differences in either parameter be-

Aims: To investigate collagen remodelling in the interstitium of the heart in patients with diabetes. Methods: Immunohistochemical study of the biopsied myocardium using type specific anticollagen antibodies (I, III, IV, V, VI) was performed in 12 patients with non-insulin dependent diabetes mellitus and six non-diabetic patients. There was no history of hypertension or coronary artery stenosis in any of the patients. Results: Noticeable accumulations of collagen types I, III, andVI in the myocardial interstitium were recognised in both groups, but little accumulation of types IV or V was found. Types I and III mainly stained in the perimysium and perivascular region, while type VI predominantly stained in the endomysium. There was no disease specific accumulation of collagen in diabetes mellitus. The percentage of total interstitial fibrosis in the myocardium was significantly higher in the diabetic group than in the control group (p < 0.05). Although the percentages of coliagen types I and VI did not differ between the two groups, the percentage type of III was significantly higher in the diabetic group than in the controls (p < 0-01). Conclusions: Collagen remodelling mainly as a result of an increase in collagen type III in the perimysium and perivascular region, occurs in the hearts of patients with diabetes.

Anomalous origin of the coronary artery can lead to angina pectoris, acute myocardial infarction or even sudden death in the absence of atherosclerosis. However, in Japan, this anomaly is usually treated medically rather than surgically. To clarify the clinical features of anomalous origin of the coronary artery in Japanese and the prognosis of such patients who are treated medically, we reviewed 56 patients with anomalous origin of the coronary arteries. The mean age of these patients was 55.9 +/- 11.5 years. Anomalous origin of the right coronary artery from the left sinus of Valsalva was seen most frequently (78.6%). In contrast, we found no cases of anomalous origin of the left coronary artery from the right sinus of Valsalva traversing between the aorta and the pulmonary trunk. A history of syncope (14.3%) and aorta regurgitation (21.4%) was frequent and serious complications during exercise stress testing occurred in 5 patients. These patients were treated medically, such as by limiting exercise or by the oral administration of medicine. During the follow up period (mean 5.6 +/- 4.2 years), death directly related to anomalous origin of the coronary artery was not found despite the lack of surgical treatment. Our results suggest that the prognosis of these middle-aged-to-elderly patients without atherosclerosis is relatively good, despite the lack of surgical treatment.

M. Impact of anti-apoptotic and anti-oxidative effects of bone marrow mesenchymal stem cells with transient overexpression of heme oxygenase-1 on myocardial ischemia. Am